Add a StreamOrdering config

presto-orc/src/main/java/com/facebook/presto/orc/DwrfStreamOrderingConfig.java

@@ -0,0 +1,40 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.facebook.presto.orc;
+
+import com.facebook.presto.orc.proto.DwrfProto;
+import com.google.common.collect.ImmutableMap;
+
+import java.util.List;
+import java.util.Map;
+
+import static java.util.Objects.requireNonNull;
+
+public class DwrfStreamOrderingConfig
+{
+    // column is the logical columns index for a table with n columns
+    // This index range from 0 to n - 1
+    private final ImmutableMap<Integer, List<DwrfProto.KeyInfo>> columnIdToFlatMapKeyIds;
+
+    public DwrfStreamOrderingConfig(Map<Integer, List<DwrfProto.KeyInfo>> columnIdToFlatMapKeyIds)
+    {
+        requireNonNull(columnIdToFlatMapKeyIds, "columnIdToFlatMapKeyIds cannot be null");
+        this.columnIdToFlatMapKeyIds = ImmutableMap.copyOf(columnIdToFlatMapKeyIds);
+    }
+
+    public Map<Integer, List<DwrfProto.KeyInfo>> getStreamOrdering()
+    {
+        return columnIdToFlatMapKeyIds;
+    }
+}

presto-orc/src/test/java/com/facebook/presto/orc/TestDwrfStreamOrdering.java

@@ -0,0 +1,39 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.facebook.presto.orc;
+
+import com.facebook.presto.orc.proto.DwrfProto;
+import com.google.common.collect.ImmutableMap;
+import org.testng.annotations.Test;
+
+import java.util.Collections;
+import java.util.List;
+
+import static org.testng.Assert.assertEquals;
+
+public class TestDwrfStreamOrdering
+{
+    @Test
+    public void testDwrfStreamOrder()
+    {
+        ImmutableMap<Integer, List<DwrfProto.KeyInfo>> columnIdToFlatMapKeyIds =
+                ImmutableMap.of(
+                        1, Collections.singletonList(DwrfProto.KeyInfo.newBuilder().setIntKey(1).build()),
+                        2, Collections.singletonList(DwrfProto.KeyInfo.newBuilder().setIntKey(1).build()),
+                        3, Collections.singletonList(DwrfProto.KeyInfo.newBuilder().setIntKey(1).build()));
+        DwrfStreamOrderingConfig config = new DwrfStreamOrderingConfig(columnIdToFlatMapKeyIds);
+        assertEquals(config.getStreamOrdering(), columnIdToFlatMapKeyIds);
+    }
+}